Motors running on diesel fuel are used in a wide variety of applications. For example, electric power generators used in remote locations (e.g., gas or oil drill sites, mining operations, etc.) are usually operated using diesel fuel. The high cost of diesel fuel has led to the development of dual-fuel supply systems for diesel fuel generators. In general, lower-cost natural gas is supplied directly into a diesel engine's manifold to reduce diesel fuel consumption. The mixture of gas-to-diesel is established/set for a particular generator motor speed which is typically the steady-state operating speed of the generator's motor. However, when motor speed must be increased (for higher load requirements) or decreased (for idle down times), the generator's diesel motor must be returned to “full diesel” operation as the adjustment of the gas-to-diesel ratio requires motor shut down. Such “full diesel” operation can greatly increase the cost of electric power generation.
In order to address this problem, gas manifold systems incorporating multiple controllable valves have been proposed for inclusion in the gas supply line of a dual fuel system. Briefly, the valves are controlled to vary the amount of natural gas being supplied. However, the supply of gas at the system's outlet tends to fluctuate as valve positions are changed. Further, each system must be custom built for each application to account for difference in supply lines, the number of diesel motors being supplied, etc.